This is a great experiment to be able to see the various components which make up what we know as “dirt”.  Including pebbles, sand, silt, clay, and soil.  This experiment takes a day or two, so don’t expect immediate results.
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What you’ll need:

• A bottle
• A handful of dirt (best from your backyard, not store bought)
• Water

What you need to do:

Put the dirt into the bottle.  Mark the line of where your soil is and add water.  Leave an inch or two of air.  Cap the bottle and shake it.  Let the bottle sit undistrubed for 24 hours.  Look at how the dirt has separated and identify the various “ingredients” that make up your dirt.  Wait for another 2-3 days, do you see more sand or clay?

For a more detailed explanation of this experiment check out the 4-H’s soil page.